Various negative ionisers have been proposed hitherto, without however giving satisfaction as regards the quality of the air which is breathed from day to day; particularly in the case of localities of small volume, such as aircraft, motor vehicles, sick rooms, dwellings, offices etc.
One of the serious disadvantages of known negative ionisers is that the volume of ambient air which they enrich with negative ions is only a small volume surrounding the said ioniser.
In certain cases a flow of air is set up so that when the air arrives at the ioniser which is to produce a negative charge in this moving air, it is travelling at a certain speed. Another disadvantage then becomes apparent, due to the fact that the air which is directed onto the ioniser is generally polluted air and consequently the device which is used will ionise both the air and also the particles of pollution. Since the ionisation is negative, these particles of pollution, which are generally large particles, will then be breathed in through the respiratory passages and will collect at the bottom of the pulmonary alveoli, being repelled by the inner walls of the upper respiratory passages which are themselves negatively charged.
This clearly presents a very grave danger to living beings, since it will result in the deposition, actually within the pulmonary tissue and the capillary circulatory system, of mould spores, fungi (mycoses), various bacteria, viruses, irritant and/or carcinogenic chemical substances, and dust of every other kind.
As regards known air-conditioning devices, the air is fed into the space intended for air conditioning with a certain amount of force, but the air so conditioned is in no way ionised, which gives rise to a sensation of heaviness and in addition it is in no way purified, thus keeping the spores, bacteria or other dust mentioned above in permanent circulation.
The negative ioniser which forms the subject of the present invention substantially reduces these various disadvantages since it enables negatively charged ambient air to be produced which is virtually free of any dust or other dangerous items, the said purified and ionised air being furthermore endowed with motion.
German patent specification No. 1,261,295 discloses an ioniser which includes an active filter, an ion absorbing arrangement, and a fan which creates a flow of air endowed with a certain amount of motion.
The ioniser which forms the subject of the present invention adopts the general structure of the ioniser disclosed in the aforementioned German patent specification whilst making a number of improvements to enable a high-performance ioniser to be obtained.